There is a football shape in my wood

The oval-shaped indentations or patches you're noticing in your plywood are known as "Dutchmen" or "oval plugs." These are typically used by plywood manufacturers to replace knots, voids, or other defects in the wood veneer. Here's why they're shaped that way:

• Grain Orientation: The oval shape allows for better alignment with the wood grain, reducing the likelihood of cracks developing along the edges of the patch. This shape helps in maintaining the structural integrity of the plywood by ensuring that the patch follows the natural grain direction, which is crucial for avoiding splitting.
• Minimal Wood Removal: The shape is chosen because it removes less wood than if a round or square patch were used, thus maintaining more of the original veneer's strength.
• Strength Distribution: The elongated shape distributes load more evenly across the grain lines, which decreases stress concentration at the ends of the patch where cracks might start.
• Manufacturing Efficiency: Oval shapes can be cut with less waste from the sheet they're derived from compared to circles or squares, and the shape is easier to orient correctly with the grain during the patching process.

These patches are often seen in plywood because they're a cost-effective way to upgrade the grade of the plywood from, say, a "B" grade to an "A" grade by filling in imperfections. They're typically applied before the final sanding and grading of the plywood panel.

If you're dealing with these in your projects, you might find them more visible after staining or painting, where the patch might absorb more stain than the surrounding wood, creating a noticeable ring. There are techniques like pre-staining or using a sealant before staining to mitigate this visual discrepancy.

Here at YUP CRAFTS we typically discard shapes that have a "football" in them unless it is in an inconspicuous place, in an undersize area that won't typically be seen, or the size of the item is so large, it is just not going to be avoided.

Let us know if you have any questions about the shapes we make, and let us make some for you!